class SpecialKey:
    def __init__(self, name: str | None):
        self._name = name

    def __str__(self):
        if self._name is None:
            return super().__str__()
        return self._name

    def __repr__(self):
        if self._name is None:
            return super().__repr__()
        return self._name


UNSET = SpecialKey("UNSET")
